BASIC BLOODBANKING PRINCIPLES Flashcards
Foreign molecules that bind specifically to an antibody or a T-cell receptor
ANTIGEN
an antigen in its role of eliciting an immune response (can elicit an immune response following antigen
binding)
IMMUNOGEN
T OR F.
All immunogens are antigens but not all antigens are immunogens
True
Characteristics of antigens: Properties that influence immune response
Size, complexity, conformation, charge, accessibility, solubility, digestibility, chemical composition
Ability to be degraded
Solubility and digestibility
More complex chemical composition = more immunogenic antigen and higher chance of eliciting an immune response
Chemical composition
What blood groups are
- Antigens are glycolipids
- More complex molecular structure because of glucose and lipids elements
ABO, Lewis, Ii, and P blood group systems
What blood groups are
○ Antigens are proteins
○ Proteins (CHONS) are complex molecules
Rh and MNSs blood group systems
Glycoprotein (immunoglobulin) that recognizes a particular epitope on an antigen and facilitates clearance of that antigen
ANTIBODY
Characteristics of IgM
Subunits: Pentamer
Heavy chain composition : Mu
Light chain composition: kappa/lambda
Intravascular
Activates classical pathway (very efficient)
Immediate spin
Do not cross the placenta
Characteristics of IgG
Subunits: Monomer
Heavy chain composition: Gamma
Light chain composition: Kappa/lambda
Crosses the placenta
Extravascular
Antiglobulin testing
Most relevant antibodies in blood banking are
IgM and IgG
Reacts at body temperature (37°C)
○ Also called warm agglutinins
IgG
Capable of destroying transfused antigen-positive RBCs
IgG
Predominant Ab produced in the secondary response
IgG
Immunoglobulin that has Rh, Duffy, Kidd, Kell blood group systems
IgG
Most commonly encountered naturally occurring Ab (ABO system)
IgM
Reacts at ambient temperature (22-24°C or colder up to 4°C)
○ Considered as cold agglutinins
IgM
Produced in response to commonly occurring antigens
○ Intestinal flora and pollen grains
IgM
Immunoglobulin that has ABO, Lewis, Ii, P, and MNS blood group
IgM
Immunoglobulin that
- Can interfere with detecting IgG by masking their reactivity
- Can exist in monomeric or pentameric form with J chain
IgM
Immunoglobulin that can increase the effect of IgG-induced RBC hemolysis
IgA
Immunoglobulin that may cause urticaria if transfused in patients with severe allergic reactions
- Due to release of histamines
- Increased in allergic reactions
IgE
Immunoglobulin that is Least significant in blood banking
● Not able to cross placenta and activate complement
● Also expressed in the surface of B lymphocytes just like monomeric IgMs
- Known to help in the activation of B lymphocytes
IgD
A type of antibody that is derived from more than one antibody-producing parent cell
Polyclonal antibodies
A type of antibody that is Produced in response to a single antigen with more than one epitope
Polyclonal antibodies